![]() Twenty years ago, water was leaking through the three-foot thick concrete dam, just to left of the spillway. I was afraid everything might just fall down in a mini-landslide. My eight year old daughter, Aubrey, was helping me, and I first got her to check that the phone in a nearby cabin was working and accessible in case of emergency. Thankfully, it was (and we had no emergency.) The leak was about two feet in from the spillway opening. It reqired placing three or four hundred pounds of concrete into the cave-like jumble of mortared rocks that form the inner core of the dam. At first, the field stone rocks rolled away like bowling balls, because decades of freezing and thawing had made the mortar at the surface totally useless. The historic stone and mortar dam was capped in the early 1950's with about a 10 inch crust of concrete, strengthened with iron reinforcing bar. So are the sides of the dam. But the inner core of fieldstone is extremely irregular, so creating a box to hold the concrete was a daunting challenge. Unless the sides of the form fit snugly against the irregular rocks, the wet concrete would simply ooze out in a mess. I had to visualize the box in space and create it. I made the bottom with a large pad of compressed foam rubber, sealing tight against the rocks. I created two corner posts with scrap wood, and then used strips of plaster lath, an inch and a half at a time, to create a tight-fitting pair of sides. The softwood lath was easy to cope into pieces that fit the irregularities of the stone. It was braced with scrap plywood, and an additional latticework of lath bracing to hold back the wet concrete. Then, as the mix was poured in bucket by bucket, I added additional boards on the front until the formation went all the way to the top of the box. It has not moved or leaked yet. |
Berkshire JournalA diary of poetry nature & interior & exterior cosmology from the Berkshires Archives
May 2021
Berkshire Living
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